The present invention relates to lock devices and, in particular, to a device for selectively preventing a gasoline pump computer from being reset.
In recent years, many previously full service gasoline stations have converted to self service type stations where the customer is permitted to turn on the gasoline pump and dispense gasoline into his own vehicle. A serious problem which has accompanied this conversion, however, has been that the gasoline pump computer which registers both the quantity of gasoline and the total cost of that gasoline, can be easily reset without the knowledge of the attendant in the course of dispensing gasoline. Consequently, a customer wishing to steal gasoline would merely have to turn off the gasoline pump, reset the gasoline pump computer and turn the gasoline pump back on again while the attendant was not watching. The total amount of the gasoline sale which would then appear on the gasoline pump would be much smaller than the actual amount of gasoline pumped. Of course the dishonest customer would only pay for the amount registering on the gasoline pump computer.
In order to solve this problem and eliminate substantial losses to individual gasoline station owners, several different mechanisms have been devised. For example, one method of preventing loss has been to remove the reset lever and replace it with a suitable lock mechanism with a key device which is retained by the attendant. Thus, a customer cannot reset the gasoline pump himself but rather must wait for the attendant. Even though this technique greatly reduces thefts, many maintenance difficulties have arisen. These difficulties mainly occur because the reset lever mechanism is so frequently used that the key device wears out in a relatively short time thus requiring frequent and expensive service calls so that repairs can be made. Furthermore, most such devices are not tamper proof and hence do not entirely stop thefts. Finally, this solution to the problem requires that at least one attendant be present to reset the pumps when customers are finished dispensing gasoline.
In order to overcome these problems and to allow one or more gasoline pump computers to be reset from a central location, electromechanical devices have been devised for attachment to the gasoline pump computer. While these devices have proven very satisfactory from the standpoint of preventing theft, these devices have generally been expensive, complex electromechanical devices involving many parts with substantial maintenance problems. Furthermore, such devices can only be used in pump housings having only one gasoline pump because their physical size prevents their use in gasoline pump housings which house two gasoline pump computers.
The present invention overcomes these difficulties by providing a simple, inexpensive and virtually maintenance free device which can be quickly and easily retrofitted into any existing gasoline pump. Specifically, the present invention provides a simple spring loaded bolt or plunger mounted to a mounted bracket. The bracket may be easily attached to a conventional gasoline pump housing with two bolts. A solenoid or other suitable device which is remotely operable is then attached to the plunger to position the plunger in either an unlocked or locked position. A link is then movably coupled to the reset lever axle in the inside of the housing so that when the reset lever axle is rotated by rotating the reset lever, the link moves in an upward direction. The link is attached to the bracket in a position so that when the plunger is in the locked position the end of the link will encounter the side of the plunger and be prevented from moving. On the other hand, if the plunger is retracted to an unlocked position then the link will be freely movable.